1997 F250 HD, 4 inch Rough Country lift. What is the maximum tire size I can run for this setup?

I keep hearing 35's will do but still rub which I don't want that no matter how minimal the rub is.

Thanks

 

I ran 35's (315/75/16) on my 95 F250 that I had. Best I could tell, it had a 4" lift. The lift and tires were already on the truck when I purchased it. The tires were real close to rubbing the front bump, so I spaced the bumper noun about a 1-1/2"

 

I should also point out that I am using stock 8 lug rims.

 

I run 35s on a 3" lift 95 F250, don't rub but I also spaced the bumper about an inch and a half

 

i ran 40 inch rubber on my 88 with a 4 inch lift and had no problems after removing the front bumper for replacement push style bumper without the side extensions.
other trucks had the same thing, but had the bumper sides trimmed for clearance.

 

just a little trim of the bumper or shim it forward and they should be just fine
but with stock rims the tire will rub the leaf spring no matter what I had 285/75 on mine with stock alcolas for awhile and they would rub occasionally